- A reaction in which metal converts the ion of another metal to the neutral atom (Remember: More reactive displaces less reactive)
Oxidation-Reduction Equation
- Known also as Redox reactions and electron transfer reactions, Redox reaction is a reaction where electrons are transferred between species
Oxidation
- Loss of electrons (OIL)
Oxidant
"Electron acceptor", causes oxidation and is reduced in the process
Reduction
- Gain of electrons (RIG)
Reductant
"Electron donor", causes reduction and is oxidised in the process
Oxidation State
- an indicator of the degree of oxidation of an atom in a chemical compound
- in monatomic ions, it will be the valence of the ion
- in polyatomic ions, it will be overall sum of charge (usually indicated by the superscript of its charge)
Fuel Cell
- Electric cell that converts chemical energy of a fuel (i.e. Hydrogen) into electrical energy
Galvanic Cell
- An "electron pump", it pumps electrons out of the negative terminal into the external circuit and "sucks" them back into the positive terminal, this occurs due to the redox equation
- Named for a device in which a chemical reaction occurs in such a way that it generates electricity
Battery
- Several cells joined together in a common outer casing
Electrode
- Conductor of a cell, connected to an external circuit
Anode
- Electrode at which Oxidation occurs, negative terminal
Cathode
- Electrode at which Reduction occurs, positive terminal
Potential Difference
- Measured in Volts (V) or Joules per Coloumb (J/C) is the difference in electrical potential energy per unit charge between two points. It is equal to the work required, per unit of charge, against a static electric field to move the charge between two points
Electrolyte
- A substance which in solution or molten conducts electricity
Salt Bridge
- Used to connect the oxdidation and reduction half cells, usually made of Potassium Nitrate.
- It used to allow the migration of ions to occur (and to keep the charge balanced in both cells so that the process can continue)
- To pick an effective electrolyte to be used in the salt bridge, it needs to not react with any ions in the solutions it is connecting and not form any precipitates with other ions
Redox Half Equations
Redox half equations are present in displacement reactions where electrons are passed from one atom to an ion.
Important things to remember:
A reductant is gaining electrons and itself is oxidised
An oxidatidant is losing electrons and itself is reduced
This is an example of a Redox reaction and its equations
Electrochemistry
Terms and Definitions
Displacement Reaction
- A reaction in which metal converts the ion of another metal to the neutral atom (Remember: More reactive displaces less reactive)Oxidation-Reduction Equation
- Known also as Redox reactions and electron transfer reactions, Redox reaction is a reaction where electrons are transferred between speciesOxidation
- Loss of electrons (OIL)Reduction
- Gain of electrons (RIG)Oxidation State
- an indicator of the degree of oxidation of an atom in a chemical compound- in monatomic ions, it will be the valence of the ion
- in polyatomic ions, it will be overall sum of charge (usually indicated by the superscript of its charge)
Fuel Cell
- Electric cell that converts chemical energy of a fuel (i.e. Hydrogen) into electrical energyGalvanic Cell
- An "electron pump", it pumps electrons out of the negative terminal into the external circuit and "sucks" them back into the positive terminal, this occurs due to the redox equation- Named for a device in which a chemical reaction occurs in such a way that it generates electricity
Battery
- Several cells joined together in a common outer casingElectrode
- Conductor of a cell, connected to an external circuitAnode
- Electrode at which Oxidation occurs, negative terminalCathode
- Electrode at which Reduction occurs, positive terminalPotential Difference
- Measured in Volts (V) or Joules per Coloumb (J/C) is the difference in electrical potential energy per unit charge between two points. It is equal to the work required, per unit of charge, against a static electric field to move the charge between two pointsElectrolyte
- A substance which in solution or molten conducts electricitySalt Bridge
- Used to connect the oxdidation and reduction half cells, usually made of Potassium Nitrate.- It used to allow the migration of ions to occur (and to keep the charge balanced in both cells so that the process can continue)
- To pick an effective electrolyte to be used in the salt bridge, it needs to not react with any ions in the solutions it is connecting and not form any precipitates with other ions
Redox Half Equations
Redox half equations are present in displacement reactions where electrons are passed from one atom to an ion.
Important things to remember:
A reductant is gaining electrons and itself is oxidised
An oxidatidant is losing electrons and itself is reduced